NEW DELHI, May 20 -- About 57 per cent of Indian districts, home to 76 per cent of India's total population, are currently at 'high' to 'very high' heat risk, according to a new study.

According to the study published on Tuesday by Delhi-based climate and energy think-tank Council on Energy Environment and Water (CEEW), the 10 states and union territories with the highest heat risk include Delhi, Maharashtra, Goa, Kerala, Gujarat, Rajasthan, Tamil Nadu, Andhra Pradesh, Madhya Pradesh and Uttar Pradesh.

It also found that the number of very warm nights has increased faster than that of very hot days in the last decade.

Very warm nights and very hot days are defined as periods when minimum and maximum temperatures rise above the 95th per...